There's a quick introduction to it here: https://www.solipsys.co.uk/new/InfiniteRamseyTheorem.html?tg26hn https://www.solipsys.co.uk/new/InfiniteRamseyTheorem.

There's a quick introduction to it here: https://www.solipsys.co.uk/new/InfiniteRamseyTheorem.html?tg26hn https://www.solipsys.co.uk/new/InfiniteRamseyTheorem.html?tg... That's just a taste of the ideas. For an entire book there's this: https://www.amazon.com/Ramsey-Theory-2nd-Ronald-Graham/dp/0471500461 https://www.amazon.com/Ramsey-Theory-2nd-Ronald-Graham/dp/04... Many books on Graph Theory will have a section about it.